public class Ex5_14{
	public static void main(String[] args){
		System.out.printf("i\t\tm(i)\n");
		for (int i = 10; i <= 100; i+=10){
			System.out.printf("%d\t\t%.5f\n", i, m(i));
		}
	}
	
	public static double m(int i){
		double sum = 0;
		double s = 1;
		for (int j = 0; j < i; j++){
			sum += s / (2*j+1);
			s = -s;
		}
		return 4 * sum;
	}
}
